Calculate minimum value over Last 12 Months

Hello Anonymous 

you can't reference a measure in a Min formula. Therefore you have to recalculate you sumamount in your new min-measure using some Summarize and addcolum. Here the solution that should work for you

MinOfSumAmount = calculate(
    minx(
        ADDCOLUMNS(
            SUMMARIZE(
                'Table';
                'Table'[Month]
            );
            "sum";
            CALCULATE(
                sum(
                    'Table'[Amount]
                );
                filter(
                    all(
                        'Table'[Month]
                    );
                    'Table'[Month]=earlier(
                        'Table'[Month]
                    )
                )
            )
        )
        ;[sum]
    );
    all('Table')
)

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Kudoes are nice too

Have fun

Jimmy